1. Field of the Invention
The present invention relates to an electrical connector. Specifically, the present invention relates to a structure of an electrical connector including a locking mechanism that ensures engaging and releasing between the electrical connector and a printed substrate.
2. Related Art
A main printed substrate mounting a CPU is mounted to a main body such as a personal computer or a server. In addition, a compact printed substrate for main memory is connected via the electrical connector on these main printed substrates.
For example, DDR3 (Double-Data-Rate3) SDRAM is a type of DRAM specification that is configured with a semiconductor integrated circuit. DDR3 SDRAM is mounted on a small printed substrate in a specified rectangular shape. This printed substrate includes an edge connector at an edge portion thereof. By the edge connector being inserted into an electrical connector on the main printed substrate, DDR3 SDRAM is electrically connected with the main printed substrate.
Generally, an electrical connector that connects a small printed substrate for memory is vertical installation type and a small printed substrate is installed in a vertical direction with respect to a main printed substrate. Then, an electrical connector is provided with a locking mechanism that engages a small printed substrate so that the small printed substrate thus mounted is not easily detached due to vibration and the like.
The electrical connector such as described above is disclosed in Unexamined Japanese Patent Application Publication No. 2005-294231 (hereinafter referred to as Patent Document 1). Patent Document 1 discloses an invention in which a height of an ejector is made to be low with the aim of minimizing an electrical connector by lowering its height and improving packaging density of the electrical connector while the small printed substrate is configured not to be easily detached from the electrical connector.
The electrical connector according to Patent Document 1 includes a square housing to which an edge portion of a small printed substrate is inserted and extracted from and a pair of headers provided to both wings of this housing. Then, the pair of headers is provided with a pair of grooves facing each other that guides both end edges of the small printed substrate.
A pair of projections facing each other is provided at an inner wall of these grooves and, when a small printed substrate is inserted, a pair of the projections is engaged with through holes that are provided at both wings of the small printed substrate. Thus, it is possible for the electrical connector according to Patent Document 1 to prevent falling out (detachment) of the small printed substrate.
In addition, Patent Document 1 discloses that the electrical connector according thereto includes a pair of ejectors that opens and closes at both wings of the housing, such that, when a pair of the ejectors is opened outwardly, the small printed substrate can be released against a pair of the projections due to the principle of leverage.
However, in a case in which strong vibrations occur to the electrical connector according to Patent Document 1, such that a pair of the projections that is engaged with the through holes provided at both wings of the small printed substrate may cross over the through holes, a pair of walls at which the pair of the projections is provided may open so that the small printed substrate may be detached from the electrical connector.
Thus, an electrical connector is demanded which reliably locks a small printed substrate so that the small printed substrate is not easily detached from the electrical connector.
In addition, since the electrical connector according to Patent Document 1 includes the pair of ejectors that opens outwardly at both wings of the housing, a pair of the ejectors occupies a part of the packaging area of the main printed substrate that mounts this electrical connector. This leads to a problem in that improvement in the packaging density is hindered.
If the ejector mechanism can be configured so as not to occupy the packaging area of the main printed substrate, space can be left for mounting electrical components on the main printed substrate, as a result of which a packaging density of the main printed substrate can be improved, and thus is preferred.